NOTES: Move NVMe entries to MI file

While here, adjust the sample setting for NVME_USE_NVD to use a
non-default setting as is typical in entries in NOTES.

Discussed with: imp
Reviewed by: manu
Sponsored by: Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D44691

(cherry picked from commit 8f7105a20697d47060dbedc966cf085a64aeced6)